A typical electrical miniplug assembly as described in German patent 101 04 288 of Richter has a dielectric plug body and a row of plug contacts fixed to the body and each unitarily formed with a flat mounting region lying on the body, a rear contact end projecting rearwardly from the respective mounting region, a front contact end projecting forwardly from the respective mounting region. A metallic plug shell surrounds the plug body and the contact ends of the contacts. A socket for such an assembly has a dielectric socket body, a row of socket contacts fixed to the socket body, and a metallic socket shell into which the plug body, plug shell, and the contact ends of the plug contacts are fittable to engage the plug contacts with the socket contacts. The shells of the plug and socket fit together in a position with the plug contacts bearing on the socket contacts to form a multiplicity of electrical connections.
In order to hold the plug in the socket, the plug shell has a broad face from which project a pair of bumps formed by strips punched out of this broad face. The socket is formed on the broad face of its shell with a pair of complementary through going holes in which the bumps engage when the plug is inserted fully into the socket, the bumps being elastically inwardly deflected during insertion, and again during removal.
A significant problem with such a connector assembly is seen with today's small pieces of electronic equipment, such as for example cell phones. The small format of the equipment requires a so-called miniplug connector that, in spite of its small dimensions, must have a large-number of contacts in order to communicate information accurately between the equipment and, for example, a programming computer. As the size of the standard flat plug is decreased it is of course necessary to shrink the width of the connectors, normally formed as small metal strips mounted flat and arranged to be deflected transversely to their planes. To get enough contacts into a small enough connector, it is desired to set them on spacing of about 1 mm, which requires that the contacts be a mere 0.5 mm in width. Such a narrow contact is extremely fragile so that the connector can readily be damaged.
A further difficulty lies in that the latch formations that secure the plug and socket together present surfaces that can snag on things. For instance if the connector cable or telephone is put in a pocket, the latch formation can catch on the pocket's lining.